Initial heating of the phenol and formaldehyde (in the presence of an acid or base to get the reaction going) produced a shellac-like liquid good for coating surfaces like a varnish.
开始加热，酚和甲醛(需有酸或碱促使其反应进行)便产生了像紫胶样的液体，能像清漆一样涂于物体表面。
Base on the knots, application of shellac varnish resin parts closed, oily putty inlaying nailhole place application.
基层上的节疤、松脂部位应用虫胶漆封闭，钉眼处应用油性腻子嵌补。
Base on the knots, application of shellac varnish resin parts closed, oily putty inlaying nailhole place application.
基层上的节疤、松脂部位应用虫胶漆封闭，钉眼处应用油性腻子嵌补。
应用推荐